Humans acquire fears in the real world (Context a). They then receive treatment for those fears in a therapist's office (Context b). Finally, they return to the real world (Context a). Unfortunately, animal research shows clearly that this a-b-a progression is one that, in its final stage (the return to Context a), leads to the renewal of an eliminated fear. Because therapists often have no choice but to follow this a-b-a progression, it is important to search for fear-elimination procedures that make fear resistant to renewal. The proposed research would exploit animal models to do so, examining a wide variety of procedures whose possible success is predicted by contemporary theory. All of the procedures use standard and well understood assays of fear in laboratory animals: Experiments 1 through 7 use the conditioned suppression (CER) procedure. Experiments 8+9 use both CER and conditioned punishment procedures. While continuing the search for procedures that resist renewal, the latter experiments provide an analysis of the role of a response contingency that is thought to be a crucial feature of participant modeling -- a type of therapy thought to be successful in treatments of fear in humans.